From Consumer Wiki

SOCIAL SECURITY

The Social Security Administration can provide information on an individual's Social Security files and give that person an estimate of Social Security earnings and benefits.

To verify that Social Security earnings are being properly recorded, consumers may call the nearest office of the Social Security Administration (U.S. Department of Health and Human Services) and request a "statement of earnings" postcard (form OAR-7004). Mail the post card to the following address:

If someone is using another person's Social Security number, report this to the Internal Revenue Service (IRS) or to the Social Security Administration. It is no problem for a consumer to receive a duplicate of the card that was lost; however, if an individual's SS# is fraudulently being used by another person, being issued a totally new SS# is a complex process and requires a court hearing to establish identity and permit issuance of a new card.